1. Field of the Invention
The present invention relates to a synchronous folding device, and more particularly to a synchronous folding device for an electronic apparatus. The synchronous folding device comprises two opposing folding members and a multi-joint rotary axle structure mounted between the two folding members. The multi-joint rotary axle structure has two ends which can be folded or unfolded synchronously so that both ends of the electronic apparatus can be closed or opened smoothly.
2. Description of the Prior Art
Nowadays, an electronic apparatus having opposing folding members (such as foldable monitor, handheld game console, PDA, cell phone, electronic book, outer casing of an electronic product, or the like) comprises a base, a foldable upper cover, and a pivotal device connected between the base and the upper cover. The upper cover is turned about the pivotal device to fold or unfold the two folding members. The pivotal device is as the axle center of the electronic apparatus so the design of the structure must consider whether the operation relative to the base is smooth or not. When the upper cover is opened to a desired angle (for example, the screen of the notebook is opened to 135 degrees), the pivotal device must have enough support force to position the screen at the operation angle.
In general, the pivotal device comprises a connection member having a spindle and another connection member having a spindle sleeve. The spindle and the spindle sleeve are connected with each other. One connection member is mounted to the upper cover, and the other connection member is mounted to the base. To consider the support strength, the two connection members having the spindle and the spindle sleeve are disposed at two opposing edges of the upper cover and the base of the electronic apparatus. For a long time, subject to the configuration of the spindle and the spindle sleeve, the support strength of the operation angle and the smooth and light operation to fold and unfolded are limited.
Due to the functional limit of the aforesaid pivotal device and the demand for a larger angle of turning, a pivotal device not having the same spindle is developed and mounted between the upper cover and the base of the electronic apparatus. The coordination of the two spindles of the pivotal device cannot be controlled so the electronic apparatus cannot be closed or opened accurately and smoothly and the demand for a light operation cannot be achieved.
Accordingly, the inventor of the present invention has devoted himself based on his many years of practical experiences to solve these problems.